1. Field of the Invention
The present invention relates to a portable electronic device having a wireless communication function, a recording medium and a communication function changeover method.
2. Description of the Related Art
There is proposed a communication device which can determine the location thereof, and automatically set an operation mode in accordance with the determined location.
For example, Unexamined Japanese Patent Application KOKAI Publication No. H10-191454 discloses a communication device having a function of receiving current location information transmitted from a gate device using a non-contact IC card, and enabling and disabling the communication function of the communication device itself in accordance with the detected location. If the current location is a location where communication is permitted, the communication device turns on the power of a communication module to enable the communication function thereof at a location where communication is prohibited in practice or a location where communication is unnecessary. Accordingly, power consumption becomes high.
Unexamined Japanese Patent Application KOKAI Publication No. 2001-320755 discloses a communication system which detects that a portable information terminal enters into the service area of the local network, allocates an extension number to the portable information terminal, thereby enabling communication using the local network. The portable information terminal uses a common communication device for a public network and an extension line. The communication device is always in activation when communication is carried out through the public network and through the extension line, and cannot suppress power consumption.
Unexamined Japanese Patent Application KOKAI Publication No. 2003-69670 discloses a cellular phone system which changes over the operation mode of a cellular phone in passing through an entrance gate. In the cellular phone system, each cellular phone has a non-contact IC card, and the entrance gate transmits a signal for instructing changeover of the operation mode to a manner mode. The cellular phone receives the mode changeover instruction signal transmitted by the gate in passing through the gate, and changes over the operation mode of the cellular phone from a normal mode to the so-called manner mode. This publication discloses that the device is set to the manner mode, but nowhere in the publication is disclosed a scheme of suppressing power consumption.
Unexamined Japanese Patent Application KOKAI Publication No. 2004-349994 discloses a cellular phone system which changes over the operation mode of a cellular phone terminal in accordance with an area and a time. This publication does not disclose a scheme of suppressing power consumption, either.
Unexamined Japanese Patent Application KOKAI Publication No. 2001-119452 discloses a wireless communication device which sequentially changes over communication mode in accordance with predetermined priorities to try communication, thereby automatically selecting any one of communication networks. The wireless communication device has a wireless circuit for PDC and a wireless circuit for PHS, and only one wireless circuit is used at one time. This publication, however, does not disclose a scheme of appropriately turning on and off the wireless circuits to thereby suppress power consumption.
Technologies for cellular phones have rapidly progressed, and there are proposed cellular phones which have not only a function of connecting the cellular phones with a public network, but also various functions, e.g., a communication function with a wireless LAN. As the number of functions increases, however, power consumption becomes high. In particular, in a case of cellular phones, it is desirable that the cellular phones should be compact in size and used for a long time without a frequent charging. However, it is difficult to fulfill all of those demands.
The foregoing publications do not disclose a scheme of suppressing power consumption in cellular phone terminals having functions of not only connecting the cellular phone terminals with a public network, but also connecting the cellular phone terminals with other networks.
Activating either one of a connection function to a wireless LAN and a connection function to a public network to suppress power consumption is possible. According to this scheme, however, an incoming call through the public network cannot be received at all when the wireless LAN is used. Unreception of an incoming call through the public network is not desirable.